Comparison of thermal injury zones in loop electrical and laser cervical excisional conization

Thirty cervical conization specimens obtained by thin-loop electric excision were compared with 30 carbon dioxide laser excisional cone specimens. Zones of thermal artifact were measured with a precise stage micrometer technique calibrated to a Zeiss standard. The mean depth of coagulation at the ectocervical margin measured 0.187 and 0.164 mm for thin loop and laser, respectively. Thermal artifact at the endocervical margin was greater with electric loop (0.295 mm) than with superpulsed carbon dioxide laser (0.137 mm). The zones of thermal injury induced by both electric loop and laser made no significant impact on the interpretation of margin adequacy.